Hello!

First I wanna say thanks to all contributors here!

I´m planning a project as follows;

Car is A6 4.2 1999

Change gearbox to 6hp26, bought one and rear diff from S6 c6. Why? Stock gearbox is giving up soon I think and this is 6gear.
Holds more power.

Single turbo kit.

One solution is running a RS6 c5 ECU, found one locally, not bought yet. But the can bus needs to change to talk to the transmission I think?

6hp26 is also found in A8 2003 ME7.1.1 also, maybe I could read the CAN protocol of those?

RS6 also use two MAFs, haven't looked into that.

Have been searching for a couple of days but no luck finding answers on CAN protocol.

I have a A6 C6 with 6hp19, could maybe read the CAN from it?

Plan B is aftermarket ECU and TCU, but no fun? 

Have read;

http://nefariousmotorsports.com/forum/index.php?topic=18881.0

http://nefariousmotorsports.com/forum/index.php?topic=19145.15

http://nefariousmotorsports.com/forum/index.php?topic=20887.0

EDIT; In this thread _nameless helps Stoti get an older ECU talk to 6hp tcu;

http://nefariousmotorsports.com/forum/index.php?topic=17945.15

Thanks

Yes, I´ve edited the post. Sorry.

Do you think it's doable?

No I want a new project. 
I'm not new into building cars, but in this Audi world.
This car also makes a great sleeper, a little bit off rust here and there 

Thanks for the information, I appreciate it. Might keep the 5hp for starters then. Replace the a-clutch/drum.
The valvebody had a crack in it when I got the car, but with help from friends it's welded/resurfaced and now running for 2 years.

Have to read up on TCU tuning 
 

Okey, thanks for sharing your opinion.

This is not a money issue, but I rather see a challenge in building a fast car on the budget.
But I don't see how this gonna cost me 10k $ to build 

Parts I don't have for the moment;

Turbo
Intercooler
Injectors
Fuel pump/line

Ecu - aftermarket or stock RS6

Run E85

Hot/cold side, can fab self.

20k $ is if I leave it to a shop to do it, right?

I plan to build by myself

Yeah YOLO

First step will be getting it to run on RS6 ecu I think  Can prove to be enough of a challenge 

Yes might need help/buy config for this, I´ve been trying to do research and this is the results so far;

Bought the RS6 box, a 4D1 907 558 F

Downloaded .bin and .xdf from https://files.s4wiki.com (thank you!) to have a look and understand what to change.
Also looked in the A8 .bin to find values below, but since the adress is not the same as in RS6 and I don´t know what value to look for I´m lost.
Have not found a .xdf with the adresses either. Any pointers?


Canver - is set to 10. But options in FR is 12,13,14? FR is for ME7.1 so thats why it´s not listed?

4D1907558F    RS6     ME7.1.1 = 10
4Z7907551R   2.7t    ME7.1.1 = 10
4E0907560    A8    ME7.1.1 = 1(with 4Z7907551R xdf, so not right)

FMOTC - is engine model? I dont understand this one, how it´s important to transmission? Shifting behaviour maybe?

4D1907558F    RS6     ME7.1.1 = 62
4Z7907551R   2.7t    ME7.1.1 = 45
4E0907560    A8    ME7.1.1 = 1(with 4Z7907551R xdf)

CWGC - should be set to 10(ZF), according to FR and forum. Stock RS6 is 01(5hp24).

4D1907558F    RS6     ME7.1.1 = 1
4Z7907551R   2.7t    ME7.1.1 = 0 or 15
4E0907560    A8    ME7.1.1 = 1 or 2 1(with 4Z7907551R xdf)


Also converting to single turbo, and therefore single o2 sensor needs some work. Read https://s4wiki.com/wiki/Tuning#Mono_O2_sensor but the
values/adresses are for Me7.1 I think. Searched the RS6 bin but only found 1A91 in one place, 1891 not at all.


The transmission(6hp26 from 2008 S6) that I bought has IMMO, so probably gonna look for another one.
Have not found how to remap/remove IMMO for a resonable amount of money by myself. Maybe a local tuner can help, haven´t asked.
PCM Flash seems to have modules for other car makes using the 6HP, maybe works.

First step will be transmission swap and convert to Me7.1.1, turbo will be later. Have a A8 4e1 907 560 Me7.1.1 box to use for this.